This invention relates to an apparatus for filtration of liquids which is particularly, but not exclusively, applicable to the preparation of beverages such as coffee.
Many designs of filtration apparatus having re-usable filter elements are shown and commonly employed materials for such filter elements have included fabrics made from metals or synthetic plastics materials. One device of this kind comprises a one piece container of synthetic plastics material having a base in which is formed a central opening through which filtrate may drain, a fine mesh filter element being supported at a small distance above the base. It has also been proposed to form ribs or baffles on the inner face of the base projecting into the space between the base and the filter element. The baffles can be used to support the filter element and also divert the downward flow of liquid passing through the filter element through a right angle when it reaches the filtrate space and cause the liquid to flow radially towards the central opening. However, this device suffers from the disadvantage that when it is used to prepare coffee by infusion, and particularly when it is used to prepare small quantities of coffee, part of the hot water introduced into the container flows straight out through the central opening so that the coffee filtrate obtained is relatively dilute. Furthermore, the cake of moist coffee grounds becomes compacted on the surface of the filter element and impedes the flow of liquid therethrough.